Cotton has been found to be very desirable for the production of a number of different products. In fact cotton product demand is increasing worldwide. The utilization of conventional cotton processing equipment makes it difficult to keep up with the demand since the equipment is relatively expensive, slow, and difficult.
As illustrated in U.S. Pat. Nos. 4,425,842 and 4,213,218, for example, cotton is handled during the entire wet finishing process in a loose batt form. Since the cotton is subjected to scouring, bleaching, finish application, drying, washing, and steaming operations during wet finishing, it is necessary that the handling equipment utilize special types of conveyors, nips, mechanical transfer devices, flow controls, and chemicals during wet finishing, as shown in these patents. This necessitates a relatively slow line speed, and there can be problems in uniform side to side bleaching of the cotton fibers.
According to the present invention, it is possible to effect wet finishing of cotton fibers (or cotton blends) at increased line speed, and utilizing equipment that need not be specialized for the handling of loose cotton fibers batts. According to the present invention, the loose cotton fibers are formed into an integral batt which has sufficient integrity to withstand further wet processing, yet remains easily transformed back into loose fibers. The integral batt is preferably formed utilizing a needling machine, which can be operated at a speed of about 24-80 feet per minute, or so that it effects about 150-560 needle impingements per square inch. The integral batt produced has a weight of about 10-32 ounces per square yard and can be subjected to the wet finishing operations--scouring, bleaching, finish applications, washing, steaming, and drying--with greatly simplified equipment and at increased line speeds. It is possible to add synthetic fibers during integral batt formation, but the amount of synthetic fibers should not exceed 40% by weight of the batt. Alternatively, the integral batt can be formed utilizing air laying equipment.
After wet finishing of the integral batt, it is desirable to break the integral batt back into wet-finished loose cotton fibers utilizing a conventional fiber opener. Alternatively, the finished integral batt may be taken up into a package, and the package further acted on during utilization of the cotton fibers in the manufacture of products. The wet finishing may be practiced in a conventional continuous batt bleaching range, except special conveyors, nips, and the like are not necessary since the integral batt may be readily transported and acted upon since it is in an integral form.
It is the primary object of the present invention to provide for enhanced capability to wet finish cotton or cotton blends. This and other objects of the invention will become clear from an inspection of the detailed description of the invention, and from the appended claims.